Many modern surgical techniques for the repair of damaged skeletal structure utilize implanted orthopedic devices affixed to the skeletal structure to lend support and rigidity thereto until the normal healing process progresses sufficiently that the structure is capable of its intended use. For example, spinal fusion surgery often involves implantation of a bio-compatible stainless steel or titanium spinal fusion implant comprised of a plurality of rods affixed to the damaged spine proximate the damaged area, usually by pedicle screws. The implant is designed to stabilize and support the spine until fusion occurs.
Presently there are several techniques available to a physician to monitor the healing or fusion process in an orthopedic implant. Common diagnostic tools include radiography, computer tomography (CT) and magnetic resonance imaging (MRI) scans, and of course exploratory surgery. Radiography, CT scans and MRI scans all are quite limited in their ability and accuracy in monitoring fusion progress due to the difficulty encountered in interpreting the scan results, even by experienced medical practitioners. Exploratory surgery is, of course, quite reliable for viewing fusion progress but is highly undesirable because of the various risks associated with an additional surgery. While some methods of measuring the progress of fusion in a patent presently exist, no known methods have the ability to monitor strain in an orthopedic device or other element (and thus the progress of the fusion taking place) under both static and dynamic loading conditions.
By carefully monitoring and quantifying the progress of spinal fusion, patients are able to return to normal activities sooner without risk of compromising the fusion process. The result is a reduction in doctor visits, decreased medical costs, and a reduction in lost work time and the attendant cost savings resulting therefrom. The average time for spinal fusion to occur is between 6 and 12 months. A real-time monitoring system for spinal fusion will eliminate the need for more costly procedures such as CT and MRI scans and provides surgeons with valuable information during the treatment process. Elimination of a single follow-up CT scan alone could save over $000 per patient. Furthermore, fusion failures can be diagnosed more quickly and accurately thereby permitting the orthopedic surgeon to take corrective measures immediately when the fusion process is not progressing space.